Land-use drivers of transport emissions – revisited

The relationship between greenhouse gas emissions and land-use has received relatively little attention in the UK since planning policy guidance on transport (PPG13) was published in 1994. Land-use and transport planning practice both continue to discuss land-use change primarily in terms of the volume of new building. Land-use policy has focused on co-location of development for related uses, while transport policy relies on vehicle technologies for reducing transport emissions. However, turnover in occupation of the existing stock of housing (‘churn’) is about ten times the rate of new build (and churn of businesses and jobs may well exceed net change in housing), but these factors have received little attention. This paper concludes that a broader concept of land-use, which takes churn into account, could improve the capacity of both land-use and transport policies to reduce transport emissions. What is good for emissions is good for most other aspects of urban policy, so such a concept could also improve the economic and social well-being of cities. As with any concept, however, its impact will depend on the policies and actions that flow from it.